#include<iostream>
#include<utility>
#include<algorithm>
using namespace std;
int main()
{
int total=1;
int N,i,j;
        cin >> N;
        pair<long int,long int> pi[N];
        for(i=0;i<N;i++)
        {
            cin >> pi[i].first >> pi[i].second;
        }
        sort(pi,pi+N);
int x=0;
int y=1;
while(x<N-1)
{
    while(y<N)
    {
        if(pi[x].second<pi[y].first)
        {

         x=y;
         y=y+1;
         total=total+1;
        }
    else if (pi[x].second>=pi[y].first && pi[x].second>pi[y].second)
       {

        x=y;
        y=y+1;
       }
       else
        y=y+1;
    }
    x=x+1;
}
cout<<total<<"\n";
return 0;
}